#include<iostream>
using namespace std;
const int mod = 1e9 + 7;
int f[10005];
int main(){
	int n;
	cin >> n;
	f[1] = 1;
	f[2] = 1;
	for(int i=3;i<=n;i++){
		f[i] = (f[i-1]+f[i-2])%mod;
	}
	cout << f[n] << endl;
	return 0;
}
